diff --git a/libavformat/mp3.c b/libavformat/mp3.c
index 42ca42fa08..01248742e0 100644
--- a/libavformat/mp3.c
+++ b/libavformat/mp3.c
@@ -63,6 +63,8 @@ static int mp3_read_probe(AVProbeData *p)
         if(buf == buf0)
             first_frames= frames;
     }
+    // keep this in sync with ac3 probe, both need to avoid
+    // issues with MPEG-files!
     if   (first_frames>=4) return AVPROBE_SCORE_MAX/2+1;
     else if(max_frames>500)return AVPROBE_SCORE_MAX/2;
     else if(max_frames>=4) return AVPROBE_SCORE_MAX/4;
diff --git a/libavformat/raw.c b/libavformat/raw.c
index f807a96f31..e7cfd7c1d0 100644
--- a/libavformat/raw.c
+++ b/libavformat/raw.c
@@ -628,8 +628,11 @@ static int ac3_eac3_probe(AVProbeData *p, enum CodecID expected_codec_id)
             first_frames = frames;
     }
     if(codec_id != expected_codec_id) return 0;
-    if   (first_frames>=3) return AVPROBE_SCORE_MAX * 3 / 4;
-    else if(max_frames>=3) return AVPROBE_SCORE_MAX / 2;
+    // keep this in sync with mp3 probe, both need to avoid
+    // issues with MPEG-files!
+    if   (first_frames>=4) return AVPROBE_SCORE_MAX/2+1;
+    else if(max_frames>500)return AVPROBE_SCORE_MAX/2;
+    else if(max_frames>=4) return AVPROBE_SCORE_MAX/4;
     else if(max_frames>=1) return 1;
     else                   return 0;
 }